Question

我需要为二进制树类编写一个复制构造函数，该类会生成给定二进制树的深层副本，但是当我执行我的复制构造函数时，我总是遇到分段错误错误，更具体地说，父节点导致问题，但我无法弄清楚这样做的正确方法。

class Node
{
 public:
  int value;;
  Node();
  Node(int v);
  Node * left;
  Node * right;
  Node * parent;
};
Node::Node()
{
  left=nullptr;
  right=nullptr;
  parent=nullptr;
  value=0;
}
Node::Node(int v)
{
  val = v;
  left = nullptr;
  right = nullptr;
  parent = nullptr;
}


class BT
{
  public:
   BT();
   BT(const BTr & t);
   Node *root;
   int size;
   Node * copy(Node *p);
   //other functions..
};

BT::BT()
{
  root = nullptr;
  size = 0;
}

//No need to consider if t.root is nullptr here
//assume t is always a non-empty valid binary tree here
BT::BT(const BT &t)
{
   size = t.size;
   root = copy(t.root); 
}

Node * BT::copy(Node *p)
{
  if (p == nullptr)
  {
    return nullptr;
  }
  Node * n = new TNode(p->val);
  n->left = copy(p->left);
  n->left->parent = n;
  n->right = copy(p->right);
  n->right->parent = n;
  return n;
}


int main()
{
  BT y;
  y.root = new Node(11);
  y.root->left = new Node(12);
  y.root->right = new Node(13);
  y.root->left->left = new Node(14);
  y.root->left->right = new Node(15);
  y.root->right->left = new Node(16);
  y.root->left->parent = y.root;
  y.root->right->parent = y.root;
  y.root->parent = nullptr;
  y.root->left->left->parent = y.root->left;
  y.root->left->right->parent = y.root->left;
  y.root->right->left->parent = y.root->right;
  y.size = 6;
  BT b(y);
  return 0;
}

Answer 1

n->left->parent = n;
n->right->parent = n;

您未先检查left或right是nullptr是否if(n->left) n->left->parent = n;，而是执行这些作业。

添加支票：

right

同样适用于cordova.plugins.diagnostic.registerLocationStateChangeHandler(function(locationMode){ switch(locationMode){ case cordova.plugins.diagnostic.locationMode.HIGH_ACCURACY: console.log("High accuracy"); break; case cordova.plugins.diagnostic.locationMode.BATTERY_SAVING: console.log("Battery saving"); break; case cordova.plugins.diagnostic.locationMode.DEVICE_ONLY: console.log("Device only"); break; case cordova.plugins.diagnostic.locationMode.LOCATION_OFF: console.log("Location off"); break; } });。

具有父节点的二叉树的C ++复制构造函数

1 个答案: